Breakdown of Napisałem podanie dla żony, aby mogła złożyć dokument.
żona
the wife
dokument
document
móc
to be able to
napisać
to write (perfective)
Questions & Answers about Napisałem podanie dla żony, aby mogła złożyć dokument.
Why is aby used here instead of żeby?
How does the grammar work after aby since the subject changes from "I" to "she"?
Just like with żeby, when the main clause subject ("I wrote") differs from the purpose clause subject ("she could"), you must use a past tense verb form after the conjunction. Here, aby is followed by mogła (the 3rd person feminine past tense of móc) to specify that the wife is the one who will submit the document.
Could I say Napisałem żonie instead of Napisałem dla żony?
Not without changing the meaning! Napisałem żonie uses the dative case and means "I wrote to my wife" (as in, you wrote her a letter or message). Napisałem dla żony uses dla plus the genitive case, which means you wrote the petition on her behalf or for her benefit.
Is złożyć the standard verb for submitting official papers?